1. Field of the Invention
The present invention relates to a lubricant coating device and an image forming apparatus, and in particular, to a lubricant supplying mechanism disposed in a lubricant coating device and an image forming apparatus.
2. Description of the Background Art
As is well know, in an image forming apparatus, such as a copier, a printer, a duplicator, etc., there is provided a lubricant supply system that supplies lubricant to a photoconductive member and an intermediate transfer belt to decrease a friction resistance generally caused during a cleaning process for cleaning the photoconductive member and the intermediate transfer belt after an image transfer process in order to prevent a porous image from being transferred therefrom in a transfer process as described in Japanese Patent Application Laid Open No. 2001-305907 (JP-2001-305907-A).
Such lubricant is scraped and supplied to the photoconductive member and/or the transfer belt by a supplying brush in rotary contact therewith. However, when the lubricant is consumed and a thickness thereof decreases, a contact condition of the supplying brush in contact with the lubricant becomes unstable, and a supplying amount thereof possibly becomes unsteady as well.
To avoid, such a problem, a prescribed system can be employed, in which a pair of elastic members, such as springs, etc., press the lubricant at both its lengthwise ends, respectively, toward the supplying brush with its axis aligned with a normal line of the supplying brush.
However, an elastic force possibly decreases as the lubricant is consumed in proportion to an expansion amount of the spring. In addition, when an abrasion amount of the lubricant is different between the lengthwise ends, supplying amount therefrom is also different from each other.
To avoid such a problem, the applicant has proposed a system capable of uniformly supplying a prescribed amount of lubricant from the entire lengthwise portion thereof as described in Japanese Patent Application Laid Open No. 2007-293240 (JP-2007-293240-A), which is submitted as IDS. Therefore, the description of the system is herein incorporated by reference.
However, it is realized that avoiding deterioration of a supplying brush as time elapses is important to maintain a preferable contact condition of the lubricant in contact with the supplying brush.
Because, when the supplying brush scrapes off the lubricant by friction therebetween and supplies it to a target, bristles of the brush sometimes deform and flattened due to the friction resistance as time elapses.
Nor can this problem be solved simply by maintaining the pressure of the lubricant against the supplying brush at a prescribed constant level using the above-described technology. Thus, for example, when the supplying brush bites hard into the lubricant, the bristles of the brush tend to flattened more. As a result, the amount of lubricant to be supplied possibly largely decreases. To minimize such flattering and deformation, the invasion amount can be decreased. However, because the contact condition of the brush in contact with the lubricant becomes unstable at light pressure because the brush is not perfectly round, lubricant supply becomes unstable.